In the trial, 524 patients were randomly assigned between 2005 and 2013 to 6 cycles of DA-EPOCH-R or R-CHOP. Among 491 eligible patients included in the current analysis, 241 received DA-EPOCH-R and 250 received R-CHOP. The current analysis presents clinical outcomes after a median follow-up of 5.2 years—the data cutoff was in November 2017.

Most patients (74%) had stage III or IV disease. The primary endpoint was progression-free survival.

Survival and Adverse Events

At a median follow-up of 5 years, there was no significant difference in progression-free survival in the DA-EPOCH-R vs R-CHOP groups (hazard ratio [HR] = 0.93, P = .65); progression-free survival was 78.9% vs 75.5% at 2 years and 68.0% vs 66.0% at 5 years. These findings were consistent when stratified by International Prognostic Index score. No difference in overall survival was observed (HR = 1.09, P = .64); overall survival was 86.5% vs 85.7% at 2 years and 77.5% vs 78.5% at 5 years.

Grade ≥ 3 treatment-related adverse events occurred in 98.3% of patients in the DA-EPOCH-R group vs 78.2% in the R-CHOP group (P < .001), with both grade 3 or 4 hematologic (97.5% vs 73.7%, P < .001) and nonhematologic (72.2% vs 43.2%, P < .001) adverse events being significantly more common with DA-EPOCH-R. Grade 3 or 4 adverse events that were more common in the DA-EPOCH-R group included infection (16.9% vs 10.7%), febrile neutropenia (35.0% vs 17.7%), mucositis (8.4% vs 2.1%), and neuropathy (18.6% vs 3.3%). Treatment-related deaths occurred in 5 patients (2.1%) in each group.

The investigators concluded, “In the 50303 study population, the more intensive, infusional DA-EPOCH-R was more toxic and did not improve [progression-free or overall survival] compared with R-CHOP. The more favorable results with R-CHOP compared with historical controls suggest a potential patient selection bias and may preclude generalizability of results to specific risk subgroups.”